Process of purifying sulphuric acid



Patented May 12, 12931 WEE STA FRANKLIN ERNEST KIlv'IBALL, C-F LQING BEACH, CAL'IFOE-NXA PROCESS OF PURIFYING SULPHURIG ACID No Drawing.

This invention relates to the oxidation of organic matter and carbon in sulphuric acid by means of heat and air and has for its object to render the process more expeditious.

In various processes sulphuric acid containin organic matter and carbon is obtained from Waste sulphuric acid sludge resulting from sulphuric acid treatment of petroleum distillates. Hitherto portions of this pres ent organic matter and carbon in recovered sulphuric acid have been oxidized by agitation with air at elevated temperatures. Frequently the chemical nature of the organic matter present in recovered sulphuric acid is such that it is more readily oxidized by hot sulphuric acid than by air. This loss of sulphuric acid thereby resulting sometimes makes it impossible to oxidize suiiicient of the organic matter to render the recovered acid fit for the treatment of gasoline, since the presence or" too much organic matter causes the gasoline to unduly emulsity with the sulphuric acid.

Instead of depending solely upon the agency of heat and air for the oxidizing action I employ antimonous sulphate to assist the oxidation of the organic matter. By this means the oxidation, being rendered very much more energetic, is ei'lected satisfactorily and with less reduction of the sulphuric acid.

It may be remarked that the antimonous sulphate alone will not oxidize the organic matter and does not therefore come under the category of oxidizing agents hitherto employed in processes of oxidation. It does not therefore render unnecessary the employment of air but "facilitates its use in oxidizing the organic matter.

In the preferred form of my invention a continuous stream of sulphuric acid having 1% antimonous sulphate and organic matter is passed through a. suitable vessel. At the same time a continuous current of air that has been heated to 500 degrees Fahrenheit is passed through the vessel. The sulphuric acid and air have separate means of ingress and egress into and from the vessel. Within the vessel the heated air agitates the sulphuric acid. The exiting air from the vessel is cooled to condense some sulphuric acid that Application filed August 14-, 1930. Serial No. 5,388.

has been evaporated. The condensed sulphuric acid is collected and continuously returned back to the vessel. The exiting sulphuric acid from the vessel is cooled as it [lows out.

Although I have herein shown and described only one process of oxidizing organic matter in sulphuric acid in the presence of antimonous sulphate embodying my inventiou it is understooc that various changes and modifications may be made herein Without departing from the spirit of the invention and the spirit and scope of the appended claims.

I claim:

1. The process of oxidizing organic matter and carbon in sulphuric acid consisting in the oxidizing action 01": air at elevated temperatures in the presence of antimonous sulphate.

2. The process of oxidizing organic matter and carbon in sulphuric acid consisting in dissolving one per cent of antimonous sulphate therein, continuously agitating the sulphuric acid in a suitable vessel by continuously supplying air at a temperature of 500 degrees Fahrenheit thereto, continuously supplying the sulphuric acid containing the an timonous sulphate thereto, continuously with drawing sulphuric acid therefrom, continuously vithdratving air therefrom, cooling same, collecting condensed sulphuric acid and continuously returning it back to the vessel FRANKLIN ERNEST KIMBALL. 

